Monitor



FIG. 1 is a rear view of a monitor showing our new design;

FIG. 2 is a left side view thereof;

FIG. 3 is a right side view thereof;

FIG. 4 is top view thereof;

FIG. 5 is a bottom view thereof; and,

FIG. 6 is a rear perspective view thereof.

The gray shading represents a metallic-looking surface. The broken lines are environmental only and form no part of the claimed design. 

The ornamental design for a monitor, as shown and described. 